Soldering iron



FIG. 1 is a front elevational view of a soldering iron showing my new design;

FIG. 2 is a rear elevation view thereof;

FIG. 3 is a left side view thereof;

FIG. 4 is a right side view thereof;

FIG. 5 is a top plan view thereof;

FIG. 6 is a bottom plan view thereof; and,

FIG. 7 is a perspective view of a soldering iron showing my new design.

The broken lines in the figures are for the purposes of illustrating portions of the soldering iron, which form no part of the claimed design. 

CLAIM The ornamental design for a soldering iron, as shown and described. 